Rock Types - Rock Classification

Rocks are classified into three main types based on their formation: sedimentary, metamorphic, and igneous. Sedimentary rocks form from compressed sediment layers, with limestone as a common example. Metamorphic rocks result from heat and pressure transforming existing rocks, such as limestone into marble. Igneous rocks form from cooled magma or lava, with granite being a notable example. Each rock type has unique characteristics and uses.

Explain the transformation of limestone into marble.

What distinguishes igneous rock from other types of rocks?